Determination of surface structures on silicon oxynitride layer and other layers grown on crystals

利用低能电子衍射（LEED）测定了SiC（0001）表面氧化氮化硅和石墨烯以及Mo（112）表面硅酸盐的表面结构。研究了碱金属原子在石墨烯表面的行为，并确定了它们的一些结构。尝试了LEED探测表面小区域的开发，并成功获得了石墨烯表面的LEED图案。此外，在场离子显微观察下，对钨尖进行了场辅助气蚀，获得了原子尖。从尖端可获得小开角的电子束。

Surface structures of silicon oxynitride and graphene on SiC(0001) and silicate on Mo(112) were determined by means of low-energy electron diffraction(LEED). Behaviors of alkali-metal atoms on graphene surfaces were also studied, and some of their structures were determined. The development of LEED probing surface small region was attempted, and LEED patterns of graphene surfaces were obtained successfully. Furthermore, fieldassisted gas etchings of tungsten tips under field-ion microscopic observation were examined, and atomically sharp tip apexes were achieved. Electron beams with small opening angles were obtained reproducibly from the tip.